Door closer

Abstract

A door closer having a return spring for accumulating a recovering force in a door closing direction at the time of opening a door for performing a braking force by a damper at the time of closing the door which comprises a closer body internally containing a mechanism for performing an operation as the damper in a body case, an adjusting arm coupled perpendicularly to a driving shaft for the damper of the closer body to be projected laterally rotatably, a coupling bracket for pivotally securing an upper frame mounting plate directly or indirectly to the end of the adjusting arm via step screws to be horizontally rotatable, and a door mounting arm projected laterally from the closer body for pivotally securing a door mounting bracket to the end of the arm via a step screw to be horizontally rotatable. Thus, the door closer can obviate a concept of mounting the closer body at the door to eliminate necessity of mounting a large closer body at the door by disposing a closer body as a damper at the pivotally securing position of the arm and the adjusting arm, thereby deleting impossibility of mounting the door closer even at a glass engaging door.

What is claimed is: 
     
       1. A door closer having a return spring for accumulating a recovering force in a door closing direction at the time of opening a door and a damper for performing a braking force at the time of closing the door, said door closer comprising a closer body including a body case internally containing a mechanism performing a damping operation,   a straight adjusting arm coupled perpendicularly and rotatably at one end to said closer body and projecting laterally therefrom,   an upper frame mounting plate extending horizontally so as to be secured to a horizontally extending portion of a door frame,   a coupling bracket pivotally securing an opposite end of said adjusting arm via a step screw to said upper frame mounting plate so that said adjusting arm is horizontally rotatable,   a door mounting bracket extending vertically so as to be secured to a vertical surface of a door mounted in said door frame,   a straight door mounting arm projecting laterally at one end from said closer body, a step screw pivotally securing said door mounting bracket to an opposite end of said door mounting arm so that said door mounting arm is horizontally rotatable,   said adjusting arm and said door mounting arm overlapping each other in a common vertical plane in a position of rest and forming an arm crossing angle at said closer body when mounted in said door frame so that said arm crossing angle increases to an angle greater than 90° when said door is initially opened and said arm crossing angle ultimately decreases in size to an angle less than 90° as said door approaches a completely open position whereby said closer body maintains said door in said completely open position upon release of said door due to a reduced recovering force on said door as compared to when said arm crossing angle is increasing towards 90°.   
     
     
       2. A door closer having a return spring for accumulating a recovering force in a door closing direction at the time of opening a door and a damper for performing a braking force at the time of closing the door, said door closer comprising a closer body including a body case internally containing a mechanism performing a damping operation,   an adjusting arm coupled perpendicularly and rotatably to and projecting laterally therefrom,   an upper frame mounting plate adapted to be secured to a horizontally extending portion of a door frame,   a coupling bracket pivotally securing an end of said adjusting arm via a step screw to said upper frame mounting plate so that said adjusting arm is horizontally rotatable,   a door mounting bracket adapted to be secured to a door mounted in said door frame,   a door mounting arm projecting laterally from said closer body, a step screw pivotally securing said door mounting bracket to an end of said door mounting arm so that said door mounting arm is horizontally rotatable,   said adjusting arm and said door mounting arm forming an arm crossing angle at said closer body when mounted in said door frame so that said arm crossing angle increases in size when said door is initially opened and ultimately decreases in size as said door approaches a completely open position whereby said closer body maintains said door in said completely open position upon release of said door,   a speed adjusting screw extending from an upper surface and a lower surface of said closer body so that said door closer may be used with both a right hand openable and a left hand openable door with access being equally available to said speed adjusting screw from a respective lower surface when said door closer is used with either a right hand openable door or a left hand openable door.